Influence of lithium oxalate doping on the calcination strength of rutile titanium dioxide

Rutile titanium dioxide has stronger density and weather resistance than anatase titanium dioxide, the overall performance is better, but the required calcination intensity is also higher. In order to reduce calcination temperature and calcination time, lithium oxalate doped metatitanic acid was used to prepare rutile titanium dioxide. Adding 0 %, 0.15 %, 0.3 %, 0.45 %, 0.6 %, 0.75 %, 0.9 % and 1.05 % lithium oxalate (calculated as lithia) to metatitanic acid (calculated as titanium dioxide) containing 0.10 % phosphorus pentoxide, 0.20 % potassium oxide and 0.2 % calcined crystal seed respectively, calcined at 800 °C, 850 °C, 875 °C and 900 °C respectively. The results show that when the doping amount of lithia is 0.3 %, the maximum temperature is 800 °C, and the calcination time is 9 h, the rutile crystal style content in titanium dioxide products can reach 99.6 %, the grain size and particle morphology meet the performance requirements of titanium dioxide (R), and the calcination strength is significantly lower than that of industrial production above 1000 °C and 10 h to 12 h calcination time. Remarkable results have been achieved in energy saving and product quality. In addition, the hypothesis that the A−R phase transition is caused by the increase of mixing entropy of titanium dioxide system is used to explain the phenomenon that lithium ions effectively promote the phase transition of rutile.